Apparatus for crimping yarn by bunching



Man]! 23, 1955 D. A. E. MATTINGLY ETAL 3,174,206

APPARATUS FOR CRIMPING YARN BY BUNCHING Filed April 3, 1963 aSheets-Sheet 1 INVENTMB March 1965 o. A. E. MATTINGLY ETAL 3,174,206

APPARATUS FOR CRIMPING YARN BY BUNCHING Filed April 3, 1963 3Sheets-Sheet 2 IDE i ALBERT Emma MRTI'INGL] D SELF} @L umsT EEG- NH MJWMamh 1965 D. A. E. MATTINGLY ETAL 3,174,206

APPARATUS FOR CRIMPING YARN BY BUNCHING Filed April 5, 1963 3Sheets-Sheet a INvE lvr s United States Patent 0 3,174,266 APEARATUS FGRCRIMPING YARN BY BUNKJHIYG Denis Albert Edward Mattingly and ReginaldSelbyG-ilchrist, London, England, assignors to The Ginger ManufacturingCompany Limited, London, England, a British company Filed Apr. 3, 1963,Ser. No. 270,448 Claims priority, application Great Britain, Apr. 4,1962, 13,036/2; June 27, 1952, 24,770/62 18 Claims. (Cl. 28-1) Thisinvention relates to apparatus for crimping yarn of the kind comprisingmeans for feeding the yarn into a passage arranged to restrict its rateof travel thereby compressing the yarn along its length forming a plugwhich fills the passage as it moves through it, the yarn being in acrimped state in the plug, means for setting the crimped yarn and meansfor withdrawing the crimped yarn from the leading end or head of thetravelling plug and winding it into a package or bobbin. An object ofthe invention is to provide means for accurately controlling the rate ofwithdrawal of the crimped yarn from the leading end or head of the plugso that the extent of forward or rearward movement of said leading endor head relatively to said passage is limited.

According to this invention an apparatus of the kind referred to forcrimping yarn is characterised in that there are provided meansresponsive to the movement of the leading end or head of the plug ofcrimped yarn from which the yarn is being withdrawn which means arearranged to vary the rate of withdrawal and winding of the crimped yarnwhereby the extent of movement of said leading end or head relatively tosaid passage in either direction is limited.

The said means responsive to movement of the leading end or head of theplug of crimped yarn may comprise a blade which projects into saidpassage in the path of movement of the plug therein and is yieldinglyloaded against the leading end or head thereof, movement of which bladeis arranged to vary the rate of withdrawal and winding of the crimpedyarn.

The means for restricting the rate of travel of the yarn through saidpassage may comprise a wheel, the periphery of which projects into anarcuate groove in an element partly encircling said wheel so as to leavea clearance between the wheel and the bottom of the groove along whichsaid plug of crimped yarn may travel round with said wheel and whichelement is provided with a slot extending outwardly from the bottom ofthe groove, and said blade extends through said slot into the groove andthrough which slot the crimped yarn is Withdrawn between the blade andthe leading end or head of the plug of yarn.

In an alternative arrangement the means responsive to the movement ofthe leading end or head of the plug of crimped yarn may comprise asource of light and light sensitive means arranged respectively onopposite sides of the path of travel or" said leading end or head of theplug of crimped yarn, which light sensitive means is arranged to controlmeans for varying the rate of withdrawal and winding of the crimped yarnso that when the source of light is cut off from the light sensitivemeans by the leading end or head of the plug the rate of withdrawal ofthe yarn is increased, but is reduced again when the light source isagain obscured.

In one arrangement two photoelectric cells are spaced apart in thedirection of travel of the bunched yarn on the opposite side thereof tothe means for directing the light on to the cells, which photoelectriccells are associated with means for controlling the rate of withdrawaland winding of the yarn so that there is no increase in rate ice ofwithdrawal until both light sensitive cells are obscured from the lightand there is no decrease in the rate of withdrawal of the yarn untilboth photoelectric cells again receive light.

In any of the arrangements referred to above the means responsive to themovement of the leading end or head of the plug of crimped yarn isarranged to con trol a change speed gear by which the means forwithdrawing and winding the crimped yarn is driven.

In the case where the means responsive to the movement of the leadingend or head of the plug of crimped yarn comprises a blade the blade maybe arranged to actuate a switch in circuit with a source of electricsupply and an electromagnetic clutch, the engagement and disengagementof which is arranged to control a two speed gear so that when the clutchis engaged the means for withdrawing the bunched yarn and winding it aredriven at a greater rate than when the clutch is disengaged.

In the case where the means responsive to the movement of the leadingend or head of the plug of crimped yarn comprise two photoelectriccells, the outputs from both of them may be connected in circuit in aspring controlled electromagnetic relay or solenoid which actuatesswitch mechanism in circuit with a source of electric supply and with anelectromagnetic actuated clutch controlling a two speed gear box whichdrives the yarn withdrawing and winding means.

Known means may be provided for laying the yarn backwards and forwardsalong the winding or take up bobbin, which means are driven through anintegrally variable gear controlled by means responsive to the variationin diameter of the package on the winder bobbin so that as the diameterof the wound bobbin increases the rate of travel of the laying meansalong the bobbin is reduced.

Other features of the invention are set out in the accompanyingdescription and claims which description is made with reference to theaccompanying drawings in which:

FIGURE 1 is a diagrammatic perspective view of the various parts of anapparatus for crimping yarn;

FIGURE 2 is a diagrammatic view of a part of the apparatus showingalternative means for controlling the rate of withdrawal and winding ofthe crimped yarn from the leading end or head of the plug of crimpedyarn;

FIGURE 3 is an electric circuit diagram showing the manner in which twophotoelectric cells are connected in circuit with a relay or solenoidwhich controls the v change speed gear for driving the yarn withdrawingand winding mechanism; and FIGURE 4 is a similar view to FIGURE 3showing an alternative circuit diagram.

The yarn 10 is drawn upwardly off the upper end of a bobbin 11 bytworollers 12, 13 driven in opposite directions between which the yarnis gripped. The yarn after leaving the bobbin passes through atensioning device 14 and then over an electrically heated body 15. Theroller 12 is fixed to a shaft 16 which drives the shaft 17, on which theroller 13 is fixed, through gearing 18. The shaft 16 has fixed to it apulley 19 driven by an electric motor 26 through a belt and pulleytransmission 21.

The rollers 12, 13 are disc like in form and project into intersectingrecesses on opposite sides of a block 22 which is secured to the lowerend of an electrically headed arcuate element 23, the inner face ofwhich is provided with an arcuate groove 24 in which part of a serratedperiphery of a wheel 25 rotates, a clearance being left between thebottom of the groove and the circumference of the wheel.

The block 22 is provided with a passage 26 which extends up from a gapbetween the upper sides of two rollers 12, 13 leading into the arcuategroove 24 near the end thereof. The serrated wheel 25 is fixed to ashaft 27 which is rotated by the following transmission.

The aforesaid shaft 16 has fixed to it a sprocket Wheel 28 which drivesanother sprocket wheel 30 through a chain and sprocket transmission. Thesprocket wheel 30 is fixed to the input shaft 31 of a variable speedgear box 32. The output shaft 33 of the gear box drives a shaft 34through a worm reduction gearing 35. The shaft 34 has fixed to it asprocket wheel 135 which drives another sprocket wheel 36 through achain 37. The sprocket wheel 36 drives the shaft 27 through bevelgearing 97. The gear ratio of the whole of this transmission is suchthat the peripheral speed of the serrated wheel 25 is considerably lessthan the peripheral speed of the rollers 12 and 13 whereby the yarn iscompressed along its length as it passes upwardly through the gapbetween the two rollers 12,. 13 into the arcuate groove 24, and buildsup into a plug which travels round with the serrated periphery of thewheel 25 in the clearance between it and the bottom of the groove. Thegroove is also so shaped as to provide a clearance between the sidewalls and the sides of the wheel.

Fixed to the upper end of the arcuate element 23 is an extension 38which has an arcuate groove 39 formed in the innerface thereof whichgroove is an extension of the groove 24 and receives the plug of crimpedyarn.

An arcuate slot 40 extends inwardly from the outer face of the extensioninto the bottom of the groove 39. The crimped yarn is drawn off theleading end or head of the plug of yarn, as it travels round with theserrated wheel by a pair of nip rollers 9 driven at a speed proportionalto the speed of the winding mechanism indicated generally at 46 the yarnpassing out through the arcuate slot 40 through a tensioning device 4 sothat the crimped yarn may be stretched before passing through the niprollers on its way to the winding mechanism after leaving the nip rollerthe yarn may be drawn over. a heated body 81 for stabilizing the degreeof crimp in the yarn. Should for any reason the yarn not be drawn awayquickly enough from the leading end or head of the plug it might becarried round by the wheel 25 again entering the groove 24 causing themechanism to become clogged or should the crimped yarn be drawn away tooquickly it will break. Thus it is important that the rate of with drawalof the yarn from said leading end or head of the plug should hear anaccurate relationship with the rate of travel of the plug of yarn alongthe groove 29. To ensure this there is disposed in the groove 39 aforked blade (not shown) the limbs of which straddle the serrated wheelwhich blade is fixed to a cranked lever 42 having a hub portion 43rotatable on the driving shaft 27 to which the serrated wheel 25 isfixed.

The hub portion 43 has fixed to it a lever arm 44 to the end of which issecured a Weight 45 thereby tending to rotate the cranked lever 42 andforked blade anti-clockwise.

The cranked lever 42 has mounted upon it a mercury switch 47 connectedby conductors 48 with an electromagnetic clutch 49, 50.

The part 49 of the electromagnetic clutch is fixed to a shaft 51 whichis driven from the shaft 16 through a chain and sprocket transmission52.

The shaft 51 has connected to it through a slipping clutch 53 a furthersprocket wheel 54 which drives a friction roller 55 of the windingmechanism through a chain and sprocket transmission 56. The otherelement of the electromagnetic clutch is fixed to a sleeve 57 rotatableon the shaft 51 and having fixed to it another sprocket wheel 58 whichalso drives the shaft 59 of the friction roller through a chain andsprocket transmission 60. The shaft 59 drives the shafts 8 of one of theaforesaid nip rollers 9 through a chain and sprocket transmission 7 andthe shaft 8 drives the shaft 6 of the other nip roller through gearing5. The two chain and sprocket transmissions 56, 6t? and the sprocketwheels 54, 58 are so arranged that when the electromagnetic clutch isnot energised the sprocket wheel 58 is freely rotating on the shaft 51and the drive is being transmitted to the shaft 59 through a free wheel53, sprocket wheel 54 and chain and sprocket transmission 56. Whenhowever, the electromagnetic clutch is engaged the shaft 59 and the niprollers 9 are driven at a faster rate through the sprocket wheel 58 andchain and sprocket transmission 60 while the device 53 associated withthe sprocket wheel 54 free wheels. The friction roller 55 bears on theouter surface of the bobbin or package 61 which is being wound so thatthe peripheral speed remains substantially constant.

If, however, rate of wind of the yarn diminishes the leading end or headof the plug of the crimped yarn will travel round with the serratedwheel 25 carrying the forked blade 39 with it until the mercury switchis swung into a position to close the circuit of the electromagneticclutch causing the nip rollers 9 and the friction roller 55 to be drivenat a greater rate as explained above and thus the leading end or head ofthe plug of crimped yarn to recede around the serrated wheels 25whereupon the forked blade 41 and lever 42 will move anti-clockwisecausing the mercury switch 47 to open and the rate of withdrawal andwinding of the yarn again to be diminished.

The yarn after leaving the heated body 81 is lead on to the bobbin 61 bya known kind of reciprocating yarn laying device 62 which is movablebackwards and forwards along a guide 63 in known manner by a scroll cam64 fixed to a shaft 65.

The shaft 65 has secured to it a friction disc 67 which is engaged by afriction wheel 68. The friction wheel 68 is secured to a sleeve 69 whichis internally splined so as to be movable along a rotatable splinedshaft 70 in a radial direction with respect to the friction disc 67.

The splined shaft is driven through chain and sprocket transmission 71from a shaft 72 which in its turn is driven through bevel gearing 73from the shaft 59 on which the friction roller 55 is mounted.

The take-up or winding bobbin 61 is mounted on a shaft 74 which isrotatably mounted at the end of an arm 75 which arm is secured to a stubshaft 76 mounted in a fixed bearing 77 and also has fixed to it a crankarm 78. The crank arm is connected by a link 79 with a pin 80 projectingfrom the side of the internally splined sleeve 69.

With this arrangement as the diameter of the package or bobbin 61increases the lever arm 75 is swung outwardly with respect to thefriction roller and in so doing moves the friction wheel 68 outwardlyfrom the shaft 65 whereby the shaft is rotated at a slower rate and thethread is moved along the bobbin 61 also at a slower rate.

The arrangement shown in FIGURE 2 is similar to that described abovewith the exception that the extension piece 38 is drilled with two holes82, 83 the axis of which intersect the groove in the inner face of theextension piece through which the serrated periphery of the wheel 25passes.

Light sources 84, 85 are disposed opposite the holes 82, 83 on one sideof the extension piece and two photoelectric cells 56, 87 are disposedopposite holes on the other side of the extension piece.

According to the rate at which the yarn is drawn away from the leadingend or head of the plug on the serrated wheel so will the leading end orhead of the plug advance past the two holes 82, 83 cutting off the lightfrom the photo-electric cells, or will recede thus uncovering the holes,thus allowing the light to fall on the photo-electric cells.

Referring to the circuit diagram shown in FIGURE 3 the two inputs of thephoto-electric cells 86, 87 are connected to one side 88 of a source ofelectric supply and their two outputs are connected to one end of a coil9 89 of an electromagnetic relay or solenoid, the other end of which isconnected to the other side 90 of the electric source of supply.

The armature 91 of the relay or solenoid is connected to one contact 92of a pair of contacts so that when the relay or solenoid i-s energisedit draws the contact 92 away from the other contact 93 against theaction of a spring 94. The two contacts 92, 93 are connected in circuitwith a source of supply and with the aforesaid electromagnetic clutch49, 50. With this arrangement assuming that the plug of bunched yarn isbeing drawn at such a rate that the leading end or head is approachingthe hole 82 both the photo-electric cells will be energised andsufiicient current will be passing through the relay or solenoid coil 89to draw the armature 91 upwards against the action of the spring 94 andthus the electromagnetic clutch will be de-energised and the nip rollers9 and take up bobbin 61 will be driven at the lesser of the two rates.

The leading end or head of the plug will first obscure the hole 82rendering the photo-electric cell 86 inoperative but the currentsupplied by the photo-electric cell 87 will be sufiicient still to holdthe armature 91 in its upper position and under these conditions the niprollers 9 and take up or bobbin 61 will still be driven at the lesser ofthe two speeds.

Should the leading end or head of the plug continue to move around withthe serrated wheel it will eventually obscure the hole 33 whereupon thephoto-electric cell 87 is rendered inoperative, the spring 94 is thenstrong enough to bring the contact 92 into engagement with the contact93 whereby the electromagnetic clutch is energised establishing -ahigher rate of drive for the nip rollers 9 and take up bobbin 61,whereupon the yarn will be drawn off the leading end or head of the plugof bunched yarn and the head will eventually uncover the hole 83 andenergise the photo-electric cell 87. However, the current supplied bythat cell alone will not be suflicient to withdraw the armature 91upwardly against the force of spring 94 and the contacts 92, 93 willremain engaged until the head of the yarn moves past the hole 82whereupon the joint currents from the two photo-electric cells will besuflicient to energise the relay or solenoid coil and draw the armatureupwardly whereon the speed of the drive for the take up spool will bediminished. Trimmers 3 are provided in the circuit so that the currentmay be adjusted to values at which the relay or solenoid will operate inthe above manner.

The arrangement shown in FIGURE 4 is similar to that described abovewith the exception that the armature 91 in addition to controlling thecontact 92 controls a further contact 95 arranged opposite a fixedcontact 96, the arrangement being such that when the contact 92 engagesthe contact 93 the contact 95 is separated from the contact 96 and viceversa. With this arrangement the output of the photo-electric cell 86 ispermanently in circuit with the relay or solenoid coil 89 and with thefixed contact 96, whereas the output from the photo-electric cell 87 isconnected to the movable contact 95. When light falls on thephoto-electric cell 86 the relay solenoid coil 89 is arranged to closethe contacts 95, 96 and to open the contact 93. If the light also failson the photo-electric cell 87 current will pass through the contacts 95,96 and the relay or solenoid coil 89 and this will result in the relayor solenoid coil continuing to be energised when the photo-electric cell86 is no longer energised by reason of being obscured from the light.

The relay or solenoid coil will have rendered the electromagnetic clutch49, 50 inoperative by opening the contacts 92, 93 and a drive will betransmitted at the lower rate to the nip roller 9 and take up bobbin 61.

If the photo-electric cell 87 is also obscured from the light the relayor solenoid coil is no longer energised and the contacts 95, 96 willseparate and the contacts 92, 93

will close energising the electromagnetic clutch and the rate ofwithdrawal of the yarn from the plug will be increased. The plug willthen commence to travel in the opposite direction uncovering the hole 83allowing light to pass the photo-electric cell 87, the contacts 92,. 93Will remain closed and the contacts 95, 96 will remain open, thus therewill be no current flowing through the relay or solenoid coil 89.

When the plug of bunched yarn uncovers the light path to thephoto-electric cell 36 the relay or solenoid coil 89 is energised andthe contacts 95, 96 close and the contacts 92, 93 will be open whichrenders the electromagnetic clutch inoperative thus slowing down therate of withdrawal of the yarn.

The plug of bunched yarn will then reach a position obscuring the lightfrom the photo-electric cell 86 but will not affect the circuit to therelay coil 89 which is held by the current supplied by thephoto-electric cell 87.

Cadmium sulphite photoconductive cells are employed since they willoperate the relay or solenoid direct without further amplification.

It will be appreciated that various modifications may be made to thedetails of the apparatus without departing from the scope of theinvention for example, the heated body 81 may be additional to or inplace of the heated element 23 for setting the yarn.

We claim:

1. Crimping apparatus, comprising feed imeans arranged to feed yarn intomeans defining a confined area to form a plug of crimped yarn, means forwithdrawing yarn from the leading end of said plug as it emerges fromsaid confined area, and means exterior of said confined area responsiveto the position of the leading end of said plug for varying the rate ofwithdrawal of the crimped yarn relative to the speed of said feed meanswhereby the extent of movement of said leading end of said plug relativeto the end of said confined area is held within predetermined limits.

2. Crimping apparatus comprising feed means arranged to feed yarn intomeans defining a confined area to form a plug of crimped yarn, means forwithdrawing yarn from the moving end of said plug, and means responsiveto the position of the leading end of said plug for varying the rate ofwithdrawal of the crimped yarn relative to the speed of said feed meanswhereby the extent of movement of said leading end of said plug relativeto the end of said cofined area is held within predeter mined limits;said last mentioned means including, light source means and lightsenstive means arranged respectively on opposite sides of the path oftravel of the leading end of the plug of crimped yarn, which lightsensitive means is arranged to control means for varying the rate ofwithdrawal of the crimped yarn so that when the amount of light reachingthe light sensitive means is diminished by the leading end of the plugthe rate of withdrawal of the yarn is increased, the rate of withdrawalof the yarn is reduced again when the amount of light reaching the lightsensitive means is increased by the retreat of the leading end of theplug.

3. An apparatus according to claim 2 wherein the light sensitive meanscomprise a photoelectric cell changes in the electrical output of whichare arranged to actuate an electromagnetic means which control the meansfor withdrawing the bunched yarn.

4. An apparatus according to claim 3 wherein two photoelectric cells arespaced apart in the direction of travel of the leading end of thebunched yarn onthe opposite side thereof to means for directing lightonto the cells, which photoelectric cells are so associated with saidmeans for varying the rate of withdrawal of the yarn that there is noincrease in the rate of withdrawal until both light sensitive cells areobscured from the light and there is no decrease in the rate ofwithdrawal of the yarn until both photoelectric cells again receivelight.

5. An apparatus according to claim 4 wherein a separate light source isprovided for each photoelectric cell.

6. An apparatus according to claim 5 wherein the means responsive to themovement of the leading end of the plug of crimped yarn controls achange speed gear by which a drive is transmitted to the means forwithdrawing the crimped yarn.

7. An apparatus according to claim 1 in which the last mentioned meansincludes a blade disposed in the path of travel of the leading end ofthe plug or crimped yarn, which blade after a predetermined movement ofthe end of the plug of crimped yarn due to the building up of the plugoperates so as to increase the speed of withdrawal of the crimped yarn,whereas after a predetermined recession of said leading end the followup movement of the blade operates to reduce the speed of withdraw-a1 ofthe crimped yarn.

8. An apparatus according to claim 7 wherein the movement of'the bladeis arranged to actuate a switch in circuit with a source of electricsupply and an electromagnetic clutch, engagement and disengagement ofwhich is arranged to control a two speed gear so that when the clutch isengaged the means for withdrawing the bunched yarn is driven at agreater rate than when the clutch is disengaged.

9. An apparatus according to claim 6 wherein the outputs of said twophotoelectric cells are connected in circuit with a spring controlledelectromagnetic solenoid which actuates a switch mechanism in circuitwith a source of electric supply and with an electromagneticallyactuated clutch controlling said change speed gear which drives the yarnwithdrawing means.

10. An apparatus according to claim 9 wherein the solenoid in additionto actuating the switch mechanism in circuit with theelectromagnetically actuated clutch also actuates switch means in aholding circuit for the relay.

11. Crimping apparatus comprising feed means arranged to feed yarn intomeans defining a confined area to form a plug of crimped yarn, means forwithdrawing yarn from the moving end of said plug and winding said yarninto a package, means responsive to the position of the leading end ofsaid plug for varying the rate of withdrawal and winding of the crimpedyarn relative to the speed of said feed means whereby the extent ofmovement of said leading end of said plug relative to the end of saidconfined area is held within predetermined limits; the last mentionedmeans including light source means and light sensitive means arrangedrespectively on opposite sides of the path of travel of the leading endof the plug of crimped yarn which light sensitive means is arranged tocontrol means for varying the rate of withdrawal and winding of thecrimped yarn so that when the amount of light reaching the lightsensitive means is diminshed by the leading end of the plug the rate ofwithdrawal of the yarn is increased, the rate of withdrawal of the yarnis reduced again when the amount of light reaching the light sensitivemeans is increased by retreat of the leading end of the plug, and meansfor laying the yarn backwards and forwards along the package beingformed which means are driven through an infinitely variable gearcontrolled by means responsive to the variation in diameter of thepackage being formed so that as the diameter of the wound packageincreases the rate of travel of the laying means along the package isreduced. 7

12. An apparatus according to claim 11 wherein said package is driven bya friction roller bearing against the outside of the wound package,which package is mounted on a part movable away from the axis ofrotation of the friction roller, which movement is arranged to controlthe infinitely variable gear driving the yarn laying device.

13. An apparatus according to claim 12 wherein said infinitely variablegear comprises a drivenfriction disc engageable by a friction wheelmovable radially with respect to the disc by said movable part on whichsaid bobbin is mounted and which friction wheel drives the yarn layingdevice.

14. An apparatus according to claim 12 wherein said friction wheel isdriven from the same means which drives the friction roller.

15. Crimping apparatus comprising feed means arranged to feed yarn intomeans defining a confined area to form a plug of crimped yarn, means forwithdrawing yarn from the leading end of. said plug,.and meansresponsive to the position of the end of said plug for varying the rateof withdrawal of the crimped yarn relative to the speed of said feedmeans whereby the extent of movement of the leading end of said plug iheld within predetermined limits; said last mentioned means includinglight source means and light sensitive means adjacent the path of travelof the leading end of said plug arranged to increase the speed ofwithdrawal of the yarn when the amount of light reaching the lightsensitive means is diminished by the leading end of the plug and todecrease the speed of withdrawal of the yarn when the amount of lightreaching the light sensitive means is increased by the retreat of theleading end of the plug.

16. Crimping apparatus comprising feed means arranged to feed yarn intomeans defining a confined area to form a plug of crimped yarn, means forwithdrawing yarn from the leading end of said plug, and means responsiveto the position of the end of said plug for varying the rate ofwithdrawal of the crimped yarn relative to the speed of said feed meanswhereby the extent of movement of the leading end of said plug is heldwithin predetermined limits; said position responsive means beingarranged and constructed to sense the position of the leading end of theplug without affecting the back pressure of the yarn within the confinedarea.

17. Apparatus for crimping yarn comprising feed means having a bight onthe discharge side thereof, confining means of short length havingstationary wall portions adjacent said bight, enclosure means having aninlet and an outlet, said inlet communicating with the discharge end ofsaid confining means, said enclosure means extending transversely awayfrom said bight, and driven conveyor means having projections extendinginto said enclosure means, whereby said mass of crimped yarn ispositively engaged at the discharge end of said confining means andconveyed through said enclosure means to said outlet, means forwithdrawing the yarn from the enclosure means, and means for controllingthe rate of withdrawal of yarn'from the outlet of said enclosure meansto maintain the position of the leading end of the plug of crimped yarnWithin predetermined limits.

18. Apparatus according to claim 17 wherein said last mentioned meansincludes a pair of photocells.

References Cited by the Examiner UNITED STATES PATENTS 2,820,988 1/58Wegener 2872 2,862,279 12/58 Pardon et al. 19-66 2,917,784 12/59 Spenceet a1. 19-66 3,096,558 7/63 Rainard et al. 281

DONALD W. PARKER, Primary Examiner.

1. CRIMPING APPARTUS, COMPRISING FEED MEANS ARRANGED TO FEED YARN INTOMEANS DEFINING A CONFINED AREA TO FORM A PLUG OF CRIMPED YARN, MEANS FORWITHDRAWING YARN FROM THE LEADING END OF SAID PLUG AS IT EMERGES FROMSAID CONFINED AREA, AND MEANS EXTERIOR OF SAID CONFINED AREA RESPONSIVETO THE POSITION OF THE LEADING END OF SAID